The present invention relates to an antenna fixture which can be used to mount a parabolic reflecting mirror fixed to a mast and to adjust the azimuth angle and elevation angle of the parabolic reflecting mirror.
Heretofore as such antenna fixtures, there have been available those shown in FIGS. 11 and 12.
In FIG. 11, a mount fixture 102 is fixedly secured to the back of a parabolic reflecting mirror 101; the mount fixture 102 is connected with a mast fixture 103; and the parabolic reflecting mirror is held at the top of a mast 105 by the mast fixture 103 and a holder 104, and fixed with bolts 106. Reference code 107 designates a supporting arm; and reference code 108 designates a converter with a primary radiator.
Here, the azimuth angle of the parabolic reflecting mirror 101 is adjusted in such a manner that, with the bolts 106 left loosened to an extent that the parabolic reflecting mirror 101 can move, the parabolic reflecting mirror 101 is allowed to rotate in the arrow A direction around the mast 105 to align the azimuth angle with a predetermined value, and then fixed by tightening the bolts 106.
In FIG. 12, a mount fixture 202 is fixedly secured to the back of a parabolic reflecting mirror 201; the mount fixture 202 is connected through a rotating axis 211 with a mast fixture 203 which is swingable around the rotating axis 211; and the parabolic reflecting mirror is held at the upper portion of a mast 205 by the mast fixture 203 and a holder 204, and fixed with bolts 206.
An elevation-angle adjusting circular-arc hole 212 is carvedly provided in the mount fixture 202 formed around the rotating axis 211 as a center; and a bolt 213 is allowed to be inserted through the elevation-angle adjusting circular-arc hole 212 and to be threadably attached to the mast fixture 203. An adjusting screw 215 is threadably attached to a supporting leaf 214 protruded from the mast fixture 203; and an adjusting leaf 216 is protrusively provided at the position opposite to the supporting leaf 214 on the mount fixture 202, whereby the tip of the above-mentioned adjusting screw 215 is allowed to abut against the adjusting leaf 216.
Here, the elevation angle of the parabolic reflecting mirror 201 is adjusted by previously loosening the bolt 213, then adjusting the adjusting screw 215, and fixing the bolt 213.
The azimuth angle of the parabolic reflecting mirror shown in FIG. 11 is adjusted by holding the peripheral edge of the parabolic reflecting mirror with hands, so that a fine adjustment cannot be smoothly performed, The elevation angle of the parabolic reflecting mirror shown in FIG. 12 is adjusted in such a manner that a coarse adjustment and a fine adjustment are performed with a single adjusting screw. Moving the mount fixture with a larger angular range requires the adjusting screw to be moved further according to the range. This results in the and adjusting work not always being sufficiently easy and not being performed with good accuracy.